Multiunit relay



lgf 3, 1943 E. R. Mom-oN Erm. 2,326,054

MULTIUNIT RELAY Filed Aug. 1o, 1940 2 sheets-sheet 1 A TTORNE Y Aug- 3, 1943- E. R. MoRToN- Erm. 2,326,054

MULTINIT RELAY Filed Aug. 10, 1940 2 Sheets-Sheet 2 /5 /6 ,4 4s /3 F/aa 3, 4/ j j 7 Il I/ I \l 52 I 5/ so sa as (34 4 k6 F IG. 4 FIGS 24 /5 24 @m29 M9 20 28 l /7 3/ @uw W E. R. Mom-ov /NVENTORSIHMSTOLL 5R A TTORNE V Patented Aug. 3, 1943 MULTIUNIT RELAY Edmund R. Morton, New York, N. Y., and Hugh M. Stoller, Mountain Lakes, N. J.,

assignors to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Appuctionugust 10,1940, serial No. 352,162

6 Claims. l(Cl. ZOO-98) 'This invention relates to electromagnetic devices and more particularly to relays of the multiunlt type.

It has heretofore been customary to manufacture relays such, for example, as relays used as line relays in telephone systems, as individual umts, each with its own pole/pieces, core, armature, coll and contact springs, to assemble such individual units on mounting plates of a relay rack and to multiple contact springs of a group of such relays together if so required. For example, relays used as the line relays in telephone systems of the cross-bar type are customarily mounted in groups of ten, each relay having two pairs of contact springs. One spring of each pair is connected to the grounded terminal of the central omce battery, the other spring of one pair is connected to a circuit individual to the line with which the relay is associated and the other 4spring of the other pair is connected to a circuit which is common to ten lines. It is thus apparent that upon the installation of such a group of ten line relays it is necessary to connect three springs of each relay in'multiple with the corresponding springs of the other relays of the group of ten thus requiring thirty soldering operations. A consideration of these requirements has led to the conclusion that a considerable simplification of the structure of relays of this type might be achieved.

It is, therefore, the object of the present invention to simplify the manufacturing and assembling of relays of the type above discussed by constructing such relays as multiunit assemblies.

In accordance with the present invention this object is attained by providing a channelshaped return pole-piece of suicient length to be used in common for five relay units and having ve cores secured to its base portion and extending forwardly between the flanges thereof. The front edges of the channel and the ends of the cores are ground flat after assembling. The magnetic circuit comprises the core, the armature and the lower flange of the return polepiece, the upper flange of the return pole-piecehaving five downwardly extending contact portions, ve individual contact members each hav ing a downwardly extending contact portion, an outer clamping plate and interposed strips of insulating material for insulating the contact members from each other and from the supporting and clamping plates. After its assembly the elements of the pile-up are held together in their assembled positions by rivets and the pile-up supporting plate is spot welded to the upper flange of the return pole-piece.

Welded to the outer face of the lower flange of the return pole-piece is an armature supporting member having live arms extending forwardly in vertical alignment with the five cores.

' Positioned with their lower edges resting upon the arms of the supporting member are five f armatures which cooperate respectively with the flve cores. Each armature carries a spring member, the upper end of which is provided with bifurcated contact portions'which cooperate with one of the individual contact members and with one of the contact portions of the common contact member and the lower portion of which is bent outwardly and hooked beneath the `corresponding arm of the armature supporting mem- `ber. The armature springs serve as grounded springs for the units of the relay and, therefore, to insure good conductivity between each supporting arm and the armature spring, the supporting arms and the hook portions of the armature springs are provided with cooperating contacts or 'connector bars. The armature springs simultaneously provide.retractile force for the armatures and also hold the heels of the armatures firmly against the supporting arms and against the forward edge of the lower channel ilange.

The relay structure above outlined provides a live-unit relay having about one-quarter of the parts which would eater into the assembly of five individual relays whereby a great saving is realized in the cost of assembly and in the cost of installation.

For a more comprehensive understanding of the invention reference, may be had to the following detailed description taken in connection with the accompanying drawings in which:

Fig. l is a top plan view, drawn to approximately double scale, of a multicontact relay constructed in accordance with the present invention with portions of two of the units omitted and a. portion of the spring pile-up broken away to better disclose features of the constructie-n;

Fig. 2 is a front elevational view of the relay disclosed in Fig. l

Fig. 3 is a view partly in cross-section taken along section line 3-9 of Fig.-2;

Fig. 4 is an exploded cross-sectional view of the spring pile-up subassembly of the relay taken along section line 4--4 of Fig. 1;

Fig. 5 is an exploded cross-sectional view of the spring pile-up subassembly of the relay taken along section line 5-5 of Fig. 1;

Fig. 6 is an exploded cross-sectional view of the spring pile-up subassembly taken along section line 6-6 of Fig. 1; and

Fig. 'I is a disassembled perspective view of an armature and its associated spring. y

Referring now to the drawings and particularly to Figs. 1, 2 and 3, the multiunit relay structure is provided with a channel-shaped common return pole-piece I of magnetic material having ve holes 2 provided in its base portion 3 through which the shouldered ends of five cores 4 are extended and firmly secured by staking as indicated at 5. A layer wound coil B having two terminal lugs 1 and 8 secured by eyelets to its rear spoolhead 9 is supported on each core. The lefthand core and coil have been omitted to better disclose the manner in which the base portion 3 of the pole-piece I is cut away as indicated at I8 and to permit the coil terminal lugs to eX- tend rearwardly beyond' the base portion 3. For assisting in retaining the coils 6 on the cores 4, the 'cores 4 are knurled at I2 for engagement in the holes in the rear spoolheads 9. l

The contact spring pile-up of the relay is a separate subassembly mountable upon the outer face of the upper ange I3 of the pole-piece I. It comprises a lower supporting plate I4 extending the full length of the flange I3, a strip I6 of insulating material, such as black phenol fibre, superimposed thereon, a common contact strip I1 of suitable spring material, such as nickel silver, superimposed on the insulating strip I6 and having five forwardly and downwardly extending contact portions |8, a soldering terminal lug 20 in engagement with the contact strip I1 near one end thereof, a second strip I9 of insulating material superimposed on the contact strip I1 and the lug 20, five equally spaced individual contact members 2| of suitable spring material, such as nickel silver, superimposed on the insulating strip I9 and each having a forwardly and downwardly extending contact portion 22, a third strip 23 of insulating material superimposed on the contact members 2| and an outer clamping plate 24 superimposed on the strip 23, and having iive forwardly and downwardly extending back stop members I5 having of the cores 4.

For holding the common contact strip |1 in its proper assembled position in the spring pile-up, strip |1 is provided with a plurality of upwardly extending embossments 25 distributed along its length, one of which is disclosed most clearly in Fig. 6, which are engaged in holes 26 in the middle insulating strip I9. Each individual contact member 2| is also provided with two downwardly extending embossments 21 which engage in holes 28 in the middle insulating strip |9 and the soldering terminal lug 20 is also provided with two upwardly extending embossments 29 which engage in holes 30 in the middle insulating strip |9.

The entire spring pile-up assembly is clamped together by rivets 3| which extend through holes in the insulating strips |6 |9 and 23, through holes in the contact strip |1 and contact mema spacing equal to the spacing between 'the axes bers 2| and through holes in the supporting plate I4 and in the outer clamping plate 24 and are headed over on the clamping plate 24. The holes in the contact strip |1 and in the contact members 2| are of sufficient diameter to permit the rivets 3| to extend therethrough without conductive engagement with vsuch strip and members. The subassembly is secured to the upper flange I3 of the return pole-piece I byspot welding the supporting plate I4 thereof to the flange at the points 32, the terminal strip I1, insulating strips I6, I9 and 23 and the outer clamping plate 24 being provided with notches as indicated at 33 to enable the spot welds to be made at certain intervals along the plate I4. When thus assembled, the backstop members I5 of the plate 24 are in vertical alignment with the cores 4, with the contact portion 22 of an individual contact member 2|, and a contact portion |8 of the'common contact strip I1 positioned on either side thereof.

Spot welded or otherwise secured to the lower flange 34 of the return pole-piece I is an armature supporting member 35 having ve arms 36 extending forwardly therefrom 'and positioned in vertical alignment with the cores 4. Positioned on the arms 36 with their lower ends or heels in engagement with the forward edge of the lower flange 34 of the return pole-piece and with their upper ends 31 positioned between the forward edge o f the upper flange I3 of the return polepiece and the inner face of the backstop members I5 are ve armatures 38. The heel pieces of the armatures are held adjacent to the forward edge of the flange 34 of the return pole-piece'v by ledges 39 struck up from the armature supporting arms 36. Secured to the inner surface of each armature is a disc 40 of nickel silver which engages with the end ofthe core 4 with which the armature is associated to prevent the armature from sticking to the core upon its attraction toward the core.

Secured to the outer surface of each armature is a spring 4|, preferably made of hard nickel silver, which is detachably secured to the armature by means of two lower studs 42 and two upper-studs 43 which may be formed as embossments on the armature and which t into holes 44 and 45 in the spring 4|. The upper studs 43 are milled or sawed to form slots, as shown at 46 in Fig. '7, and the holes 45 in the spring 4| are formed with horizontal upper edges.V In assembling the spring 4| on the armature 38 the studs 43 are slipped through the holes 45 in the spring and the spring is then pushed downwardly until the upper straight edges of the holes 45 are seated in the bottoms of the slots of the studs 43 and the spring is thus embraced between the heads of such studs and the outer face of the armature at which time the holes 44 in the spring will be aligned with the studs 42 and such studs will then enter such holes. 'I'he spring 4| is now held against the outer face of the armature by the heads of studs 43 and is held from moving lengthwise or laterally with respect to the armature by the studs 42.

The upper end of the spring is slotted to form two bifurcated contact portions 41 and 48 and a central tongue 49 which engages with the inner face of a backstop member |5 and which serves with the backstop member I5 to determine the normal air-gap between the armature 38 and the end of the core 4 with which it is associated. The contact portions 41 and 48 are provided with suitable contacts which cooperate with contacts 38 as previously described and the heel of the armature seated on the arm 36 of the support 35 between the ledge 39 and the forward edge of the flange 34 of the return pole-piece, the loop portion 50 of the spring is engaged beneath the end of arm 36 with itsA connector bar 5I in engagement with a connector bar 52 of contact material secured to the underside of the arm 36. The loop portion 50 of the spring being pretensioned by bending as disclosed in Fig. 7, the spring in its assembled position as disclosed in Fig. 3, biases the armature toward the backstop member I5 and exerts sufcient downward force to hold the heel of the armature ilrmly against the supporting arm 36 and against the forward edge of the ange 34 of the return pole-piece thereby reducing the reluctance of the air-gap between the heel of the armature and the return polepiece. To prevent the armature from slipping laterally with respect to the supporting arm 36,

the width of the opening ln the lower end of the armature spring 4I which forms the loop portion 5U is only slightly greater than vthe Width of the enlarged portion 53 of the supporting arm 36 as best disclosed in Fig. 2.

To insure that when any one coil is energized only the armature associated with the core on which such coil is supported will be attracted, the cross-sectional area of the core and of the armature are made less than the cross-sectional area of the return pole-piece so that magnetic saturation occurs in the core and in the armature rather than in the return pole-piece. Consequently there is no saturation in the common parts of the magnetic circuit and, therefore, negligible coupling between the units of the relay occurs. Such coupling is known as magnetic crossiire and in the case of marginal relays must be held at times to less than one per cent of the magnetomotive force of the operating coil. When any armature becomes attracted its armature spring 4I, which is connected to ground over connector bars 5I and 52, through the return polepiece I and the relay rack to which it may be secured bythe screws 54, engages its contact portions 4l and 48 with the contact portion 22 of an individual contact member 2| and with the contact portion I8 of the common contact strip I1 whereby ground becomes connected to the individual contact member 2| and to the common contact strip I'I and the soldering lug 20 connected therewith.

The relay requires very little adjustment in service but an adjustment of the contact portions 41 and 48 of the armature spring 4I may be made by removing the spring from the armature, bending such portions and reassembling the spring on the armature as previously described. It is to be noted that the method employed for securing the armature spring to the armature in no manner iiexes the armature spring to upset the adjustment of its contact portions 41 and 48 as would be the case were the spring 4I secured to the armature by rivets or screws.

What is claimed is:

l. In a relay, a return pole-piece, a core supported thereby, a coil on said core, an armature supporting arm secured to said return pole-piece,

an armature supported on said arm with its heel resting on said arm and against the pole face of said return pole-piece, and a leaf spring prebent into a V-shape having one leg thereof secured to said armature and having the portion thereof near its bend cut away to form a loop in the other leg thereof through which said arm extends and conductively engaged with'the outer surface of said arm whereby said spring normally biases said armature into its retracted position and engages the heel thereof with said arm and with the pole face of said return pole-piece.

2. In a relay, a return pole-piece, a core supported thereby, a coil on said core, an armature supporting arm secured to said return pole-piece,

. an armature supported on said arm with its heel resting on said arm and against the pole face of said return pole-piece, and a leaf spring prebent into a V-shape having one leg thereof secured to said armature and having the portion thereof near its bend cut away to form a loop in the other leg thereof through which said arm extends and conductively engaged with the outer surface of said arm and with the inner side edges of said loop engaged against the edges of said arm, whereby said spring normally biases said armature into its retracted position, engages the heel thereof with said. arm and the pole face of said return polepiece and centers said armature with respect to said core.

3. In a relay, a return pole-piece, a core supported thereby, a coil on said core, an armature supporting arm secured to said return pole-piece, an armature supported on said arm with its heel resting on said arm and against the pole face of' said return pole-piece, a leaf contact spring prebent into a V-shape having one ieg thereof secured to said armature 4and having the portion thereof near its bend cut away to form a loop in the other leg thereof through which said arm extends and engaged with the outer surface of said arm, whereby said spring normally biases said armature into its retracted position and engages the heel thereof with said arm and the pole face of said return pole-piece, and a pair of cooperating connector bars one secured to the underside of said arm and the other secured to the loop portion of said spring for insuring good conductivity between said spring and said return pole-piece.

4. In a relay, a return pole-piece7 a core supported thereby, a coil on. said core, an armature cooperative with said core and said return polepiece having two pairs of studs embossed from its outer face, one pair of said studs being transversely slotted adjacent the outer face of said armature and the other pair of said studs serving as locking studs, and a spring detachably secured to said armature for holding said armature in a pivoted relationship with said return pole-piece having a first pair of holes through which said slotted studs extend and having a second pair of holes through which said locking studs extend when said spring is moved to a position to engage the upper edges of its first pair of holes in the bottoms of the slots of said first pair of studs.

5. A multiunit relay comprising a channelshaped return pole-piece, a plurality of cores supported thereby, a coil on each of said cores, a member secured to one flange of said pole-piece having a plurality of armature supporting arms, an armature supported on each of said arms opposite each of said cores, a spring pile-up secured to the other flange of said pole-piece comprising as many pairs of contacts as there are armatures,

one contact of each pair being an individual contact and the other contact being a multiple from a common contact strip, and a spring secured to each of said armatures for bridging engagement with an associated pair of contacts of said pile-up and having an outturned portion engaged beneath the associated armature supporting arm whereby said armature is held in its retracted position with its heel held against the pole face of said one flange. y

6. A multiunit relay comprising a return polelpiece, a plurality of cores supported thereby, a.

coil on each of said cores, an armature cooperative with each of said cores, a spring pile-up secured to said return pole-piece comprising a lower supporting plate, a contact strip having a contact portion associated with each of said armatures, a layer of individual contact members associated respectively with said armatures. an outer clamping plate provided with a backstop extension for each of said armatures. strips o! insulating material interposed between said lower supporting plate, said contact strip, said layer of contact members and said outer clamping plate, and means for clamping said elements of said pile-up together, and a spring secured to each of said armatures for bridging engagement with the contact portion of said contact strip and the individual contact member associated with each of saidcores.

EDMUND R. MoRToN.

HUGH M. STOLLER. 

